Polk Audio LSi15's and LSiC AV Rx suggestions

Cshah

I recently bought the Polk Audio LSi15's tower speakers and LSiC center channel and a PSW125 sub-woofer. I was looking for an AV Receiver to drive these bad boy's. I looked online and mostly all are 8 ohm loads and I could not find a true 4ohm Rx. Some have a 6 ohm setting but I am not sure how will that work.

:sad::sad::sad:

PLEASE HELP! Thanks,

-C

tonyb

Welcome, most receivers cannot drive 4 ohm speakers. What you need is a receiver with 5.1 preouts and an additional amplifier. Look at some threads or do a search on powering LSI's to learn more.

Cshah

Can anyone please post a link or a list the setup they have with a similar speaker system?

Meanwhile I will hunt through the forums to find out the ideal setup. Sighhhh! Should've looked before I bought these.

Btw, since I'm a noob, can someone explain the difference between the 4 and 8 Ohms (which is better and why?)

Thanks
-C

EndersShadow

Cshah wrote: »

Can anyone please post a link or a list the setup they have with a similar speaker system?

Meanwhile I will hunt through the forums to find out the ideal setup. Sighhhh! Should've looked before I bought these.

Btw, since I'm a noob, can someone explain the difference between the 4 and 8 Ohms (which is better and why?)

Thanks
-C

This might help. Here is what I have right now

Fronts: LSi 15's
Center: LSiC
Surrounds: LSi F/X
Reciever: Integra DTR 5.9
5 channel amplifier: Carver AV-705x

Here is what I suggest you look at: Onkyo TX-NR709 from Accessories4less.com (if they have any, if not look at the TX-NR809). You basically want to find a good reciever with the features you want, and you can ignore the power ratings as long as it has pre-outs. Either of those Onkyo's have pre-outs.

The reason I suggested that particular site is its an authorized reseller of refurbished Onkyos (they also sell Denon, and Marantz). The refurbished units come with a manufacture warranty that is only 1 year less than if you bought new. Given it is a manufacture warranty I feel losing a year for the cost savings may just be worth it IMHO. However YMMV.

Now given right now you just have the front three I would still try to find a 5 channel amp on the used market. The reason for this is that unlike recievers which are constantly upgraded, new tech added, etc, power amps havent changed in a LONG LONG time. So you can get a nice power amp used for a pretty low price compared to new. Now one big difference between an AVR and a dedicated amp is going to be the wattage.

AVR's tend to fudge the numbers on their wattage per channel and normally provide a much lower number with all channels driven than a power amp. The reason is that a dedicate amps rating is with all channels driven whereas a AVR is normally with just 2 channels driven. That makes a big difference.

To put that in perspective my 5 channel Carver amp provides 125x5 watts whereas my Integra provides 90x7. My Carver can get my LSi 15's can push upwards of 110db when listening in stereo before my amp starts to have ANY trouble. The same would NOT be true with my Integra (which isnt rated for 4 ohm speakers anyway)

Some brands to look at are ones like: B&K, Carver, Rotel, Parasound, etc. A great place to look for these amps would be on Audiogon.com or usaudiomart.com as well as ebay.

nwohlford

One of the few receivers that I have ever seen give true 4 ohm specs to all channels is the Sherbourn SR-120 (it is 1.3b HDMI). The front three channels are rated 175 watts into 4 ohms. The four rear channels are rated at 100 watts into 4 ohms. Most receivers can do close to rated power over three channels, but I am sure if that is true with 4 ohms. Will you have more than a pair of the LSi15s and a LSiC?

You can get these directly through the parent company (Jade Designs) for $800. You may be able to find them a little cheaper used. I have never heard one of these, so I can't recommend it. It does weigh 77lbs which is quite impressive for an AVR.

There are other AVRs that probably could do it (the Integra AVRs that are 4 ohm certified, the top of the line AVRs from the common brands, and some of the AVRs from more boutique companies).

I am personally using an amp (Adcom GFA-7400 rated 150 watts into 4 ohms) with my LSi9s and LSiC which is definitely adequate for my small to medium sized room. I have used it with an AVR using preamp outs and a pre/pro.

Cshah

Wow this was so comprehensive and well explained. Thanks a lot!! I will look at the websites and try to get these bad boys powered up soon. Thanks a lot for the explanation!

-C

EndersShadow wrote: »

This might help. Here is what I have right now

Fronts: LSi 15's
Center: LSiC
Surrounds: LSi F/X
Reciever: Integra DTR 5.9
5 channel amplifier: Carver AV-705x

Here is what I suggest you look at: Onkyo TX-NR709 from Accessories4less.com (if they have any, if not look at the TX-NR809). You basically want to find a good reciever with the features you want, and you can ignore the power ratings as long as it has pre-outs. Either of those Onkyo's have pre-outs.

The reason I suggested that particular site is its an authorized reseller of refurbished Onkyos (they also sell Denon, and Marantz). The refurbished units come with a manufacture warranty that is only 1 year less than if you bought new. Given it is a manufacture warranty I feel losing a year for the cost savings may just be worth it IMHO. However YMMV.

Now given right now you just have the front three I would still try to find a 5 channel amp on the used market. The reason for this is that unlike recievers which are constantly upgraded, new tech added, etc, power amps havent changed in a LONG LONG time. So you can get a nice power amp used for a pretty low price compared to new. Now one big difference between an AVR and a dedicated amp is going to be the wattage.

AVR's tend to fudge the numbers on their wattage per channel and normally provide a much lower number with all channels driven than a power amp. The reason is that a dedicate amps rating is with all channels driven whereas a AVR is normally with just 2 channels driven. That makes a big difference.

To put that in perspective my 5 channel Carver amp provides 125x5 watts whereas my Integra provides 90x7. My Carver can get my LSi 15's can push upwards of 110db when listening in stereo before my amp starts to have ANY trouble. The same would NOT be true with my Integra (which isnt rated for 4 ohm speakers anyway)

Some brands to look at are ones like: B&K, Carver, Rotel, Parasound, etc. A great place to look for these amps would be on Audiogon.com or usaudiomart.com as well as ebay.

EndersShadow

It would also be good for us to know the size of your room as well as with a small room you can get by with a dedicated amp with less power than you may need in a larger room.

Another reciever suggestion I had NOT mentioned was that some of the high end Pioneer Elite SC units have been used by forum members to run their LSi speakers.

Personally thats a choice you can make if you want one unit to do it all, I personally just like the Audyssey EQ as I am use to it and Pioneer uses their own equally good MCACC EQ but thats not my personal cup of tea. YMMV.

Cshah

nwohlford wrote: »

One of the few receivers that I have ever seen give true 4 ohm specs to all channels is the Sherbourn SR-120 (it is 1.3b HDMI). The front three channels are rated 175 watts into 4 ohms. The four rear channels are rated at 100 watts into 4 ohms. Most receivers can do close to rated power over three channels, but I am sure if that is true with 4 ohms. Will you have more than a pair of the LSi15s and a LSiC?

You can get these directly through the parent company (Jade Designs) for $800. You may be able to find them a little cheaper used. I have never heard one of these, so I can't recommend it. It does weigh 77lbs which is quite impressive for an AVR.

There are other AVRs that probably could do it (the Integra AVRs that are 4 ohm certified, the top of the line AVRs from the common brands, and some of the AVRs from more boutique companies).

I am personally using an amp (Adcom GFA-7400 rated 150 watts into 4 ohms) with my LSi9s and LSiC which is definitely adequate for my small to medium sized room. I have used it with an AVR using preamp outs and a pre/pro.

Hi, No I do not plan to have anything more than the 2 LSi15's and LSiC. I have a PSW125 subwoofer as well. I am looking at the external amp option as well. Can you suggest an AVR with adequate number of pre amp out channels? Thanks for your help.

Cshah

The room size is approximately 25ft * 18ft

Tankman

@Cshah..if you can get your hands on a Carver used or anyone of the amps that EndersShadow listed jump on it.

stretchl

I would add the adcom 555 and 555ii to that list. Available for just over $300 on eBay.

codyc1ark

Welcome to the LSi series! Since you asked, I'll let you know what I'm running, but you WILL need an amp to avoid damage to your speakers or the AVR. Good luck!

Pioneer SC-25
Adcom GFA-7000 (200w x 5 @ 4ohms)
LSi9, LSiC, and some Mirage surrounds (needed something smaller for placement reasons)
That about does it for powering the setup, but I also run a power conditioner, sub eq, a couple of different players, and a Squeezebox.

Cshah

Does anyone have an input on Emotiva UPA-5 or XPA-3? (I'm assuming I might need 5 channel amp so XPA-3 might be redundant by itself)

tonyb

Many here use them, and many also prefer other brands too. Yes, Emo amps will power those speakers but many agree there's better options out there sound quality wise. Use the search function for emotiva and thumb around a few threads.

Tankman

tonyb wrote: »

Many here use them, and many also prefer other brands too. Yes, Emo amps will power those speakers but many agree there's better options out there sound quality wise. Use the search function for emotiva and thumb around a few threads.

+1..I use two EMO UPA-1's for my LSI-15's in a 2.1.They are ok,Like Tonyb said better out there.Not knockin EMO the XPA-5 I have will stay for HT use.Will upgrade the UPA-1's to a Nice BK Butler before the end of the year.

Cshah

I'm back again with a few questions. So for the AV Receiver I bought the Onkyo TX NR717. It has pre-amp outs and a 4ohm impedance setting as well. Got a pretty good deal or so I think(599 USD) on amazon. However, in relative volume level mode, I'm having to crank the volume up to almost -40dB to get any sound from the tower speakers (Haven't yet connected the LSiC). Is this expected / normal? I ran the Equalizer autotune setup but evidently didn't do a very good job. Thanks, for the help guys. (Educate the noobs )

tonyb

Well, we've been trying to educate you. You need an amp for LSI speakers is the bottom line. Your going to risk damage to the speakers or receiver or both. The 4 ohm setting on the receiver limits the receivers power to keep it from over heating and going into protect mode. It does not deliver more power , which is what a 4 ohm speaker needs. That 4 ohm switch on most receivers is to benefit the receivers well being, not deliver more current to the speakers. You have to turn the volume up to get the receiver to generate more current to power the speakers, your not even hitting their potential with that receiver. After you keep turning it up higher and higher, it will get to a point where it has nothing left and will shut down. Also by trying to drive your new speakers with an under powered source, your introducing distortion by turning the volume up, and that too will kill speakers. So again, get an amp for every channel an LSI is on, with the possible exception of the LSI 7's. Also, you need to setup the receiver, read the manual cover to cover, twice, so you get a good grasp on what every setting does. Good luck to you, and forgive me for being bold in my response. I just hate to see someone toast a speaker, they aren't cheap these days.

If you can't afford an amp now, keep the volume levels down until you can.

cfrizz

We have told you from the outset that the majority of receivers don't have the power to run any of the LSIs by themselves which is why you now have a receiver with preouts. Now get yourself an Emotiva XPA 3-5 channel amp to give them the power that they need to run to their full potential. And in the meantime, keep the volume low while listening until the amp arrives. You have bought some very nice speakers that weren't cheap, now you are going to have to spend more money to be able to power them properly.

Cshah

tonyb wrote: »

Well, we've been trying to educate you. You need an amp for LSI speakers is the bottom line. Your going to risk damage to the speakers or receiver or both. The 4 ohm setting on the receiver limits the receivers power to keep it from over heating and going into protect mode. It does not deliver more power , which is what a 4 ohm speaker needs. That 4 ohm switch on most receivers is to benefit the receivers well being, not deliver more current to the speakers. You have to turn the volume up to get the receiver to generate more current to power the speakers, your not even hitting their potential with that receiver. After you keep turning it up higher and higher, it will get to a point where it has nothing left and will shut down. Also by trying to drive your new speakers with an under powered source, your introducing distortion by turning the volume up, and that too will kill speakers. So again, get an amp for every channel an LSI is on, with the possible exception of the LSI 7's. Also, you need to setup the receiver, read the manual cover to cover, twice, so you get a good grasp on what every setting does. Good luck to you, and forgive me for being bold in my response. I just hate to see someone toast a speaker, they aren't cheap these days.

If you can't afford an amp now, keep the volume levels down until you can.

Thank you tony. I know it's getting a little annoying. Thank you for your suggestions. This just affirms that I did not receive bad speakers. Sorry for the useless questions.

cfrizz wrote: »

We have told you from the outset that the majority of receivers don't have the power to run any of the LSIs by themselves which is why you now have a receiver with preouts. Now get yourself an Emotiva XPA 3-5 channel amp to give them the power that they need to run to their full potential. And in the meantime, keep the volume low while listening until the amp arrives. You have bought some very nice speakers that weren't cheap, now you are going to have to spend more money to be able to power them properly.

Thank you for your suggestion. Sorry for re repeating questions. You guys do a good job helping us out.

Cshah

What is the difference between the Rotel RB985 and Rotel RB985 MK2? And what would be a good bargain price on either one of these?

Thanks
-C

tonyb

I think not much difference, but the MK2 is supposedly suppose to run cooler than the mk1 which ran fairly warm to hot. So if your going to put one of these in a cabinet, hit the mk2.